Weil Mclain Ultra constant problems

Kdg0363

I had an Ultra 155 installed in Jan 10 and it worked great for three months before shutting down for the summer.  However, this winter has resulted in four visits from the boiler expert.  Great guy with great service, but continued problems as follows:



1) Overheating - on two occasions the boiler was in the middle of a cycle when the temp shot up to 200+ degrees.  Lots of banging (i assume as it began making steam) and had to be manually reset.



2) Often the system will begin banging when it first starts-up (water temp below 80 degrees).  The system generally resets itself and starts on the second cycle.



3) Recently the system cycles through a pre-purge / ignition / post-purge (over and over) but does not ignite and heat.  Generally i have to set the thermostat to no heat and them back to break the cycle.



4) The amount of pump / water noise in the house is loud.  Most of my neighbors also have baseboard heat and i hear the pipe's expansion noise.  But in my house, it is very evident that a circulator pump is moving water through the house.



The unit runs as a single zone system.  The air trap is a SuperVent. The supply pump is a Taco 007.



The diagnosis is air in the system.  The fast overheating would seem to support that diagnosis.  I am not certain about the automatic resets when the unit first starts or the pre-purge / post purge cycling.  I have thoroughly flushed the system twice and all rooms are receiving heat.  If it is trapped air - what can i do to get the air out of the system as it seems that the SuperVent does not release any air.



Thanks for any suggestions.  I posted a few pictures as well.

icesailor

Ultra Piping:

I haven't installed an Ultra but something doesn't look right about the piping. I don't have a piping manual for it but I'm sure that it is incorrect. It's supposed to be primary/secondary but it looks strange to me. You are not getting enough flow through the boiler hence, it is flashing over into steam.

Look at the Manufacturers piping diagram.

Jean-David Beyer

I am just a homeowner, but...

I do have a W-M Ultra 3 80. I cannot tell what your problems are for sure, but there are a few curious things.



1.) Your closely-spaced Ts are funny. The right hand one that connects the supply to the secondary loop. That T is sideways which will probably make the flow incorrect.



2.) I cannot see where your supply and return temperature sensors are. The supply should be on the right of the right-most T, and the return sensor sould be on the left of the left-most T. Both sensors should be in the secondary loop, at least 6 pipe diameters away from the closely-spaced Ts, but no more than three feet.



3.) Do you have the outdoor reset connected? If not, why not?



4.) I do not see a Low Water Cut Off in your system. W-M say the U-control will detect low water and shut down your system, if local codes permit. My installer put in a M&M probe-type LWCO. I do not know what the code thinks around here, but I am glad to have it.



Your boiler should not go up to 200F unless you have the U-control board set funny (or it is defective or wired incorrectly). Maybe you could set it up that hot if you wanted especially fast recovery from an indirect hot water heater, but it does not appear as though you have one. Have you studied all the settings on the U-control board in your Installation manual? Is your unit an Ultra-3 or and Ultra-3 UE?



Do you have the U-control programmed so that both the boiler circulator and the secondary circulator run when the thermostat calls for heat? If not, the temperature should rush up pretty fast and the U-control would lock out your system, at least for a while. It might think your water level was low.



My system never bangs. I have three "zones." One is across the primary (boiler) loop and goes to the indirect hot water heater. The other two are in the secondary loop. One zone goes to an in-slab radiant zone, and the other goes to a small zone with oversized baseboard emitters. The radiant slab zone modulates between 75F in warm weather to 120F if it gets down to 6F (which as far as I know, it never does). The baseboard zone modulates between 110F and 135F.



When I get air in it, it sounds like air, not banging, not rushing. I get no expansion noises in the radiant slab (1/2" copper tubing in concrete). I do get some expansion noise in the baseboard zone if it cycles on and off. In very cold weather, it modulates up and down but not on and off. I do not know if I could tell air noise from cavitation. I do not know what a SuperVent air trap is. Do you mean a SpiroVent air eliminator? If it is at all like my Taco 49-125, there is a screw that can be used to close the air vent. Mine should be open 1 1/2 turns. I do not know about SpiroVents. Where is the green 007 in relation to the expansion tank? Does it pump away from the tank?

Mark Eatherton

Sawzall Surgery...

I've never seen a gravity check used in a mod con boiler. Must be an old school plumber in a new school world...



As others have noted, it is not set up correctly as it pertains to primary/secondary piping.



The upper pump is installed upside down. Can't tell if it is pumping in the right direction or not. See if you can find a directional arrow and tell us whether it flows R to L or L to R.



Sounds as if the installer is afraid of them new fangled controls as well, and has it set up like an old conventional cast iron boiler. One temperature. 180 degrees F or nothing...



I would get rid of the gravity check, correct the piping deficiency, flip the pump up right, and replace the pump on the boiler. Taco OO pumps can occasionally have "issues" and intermittent situations where they will not start. If that happens, the boiler will bang and pop and go off on high limit.



Also, if the outside sensor is not hooked up, have them do so and program it for 140 minimum at 60 degrees F outside, and 180 degrees F when the outside air is 0 degrees F.



You can down load the installation and maintenance manual on line, and see the correct way to install it.



If your plumber isn't comfortable doing this, then maybe you need to consider finding one that knows how to read and follow manufacturers instructions.



ME

lchmb

size

What size is the circulator on top of the unit (black one)?

Jean-David Beyer

That Flow Check valve is OK.

"I've never seen a gravity check used in a mod con boiler. Must be an old school plumber in a new school world..."



Weil McLain specifies one of those in that location, and I have one. It is not clear from the photograph if it is pointing the right way or not, because I cannot see the arrows on the casting. I have one in my system.



"The upper pump is installed upside down. Can't tell if it is pumping in

the right direction or not. See if you can find a directional arrow and

tell us whether it flows R to L or L to R."



True. Not good.



"Sounds as if the installer is afraid of them new fangled controls as

well, and has it set up like an old conventional cast iron boiler. One

temperature. 180 degrees F or nothing..."



I have no idea about that. You have to look at the settings to tell that, but if the guy set up the primary-secondary piping like that, put the green circulator in upside down, etc., I would not be surprised.



"I would get rid of the gravity check, correct the piping deficiency,

flip the pump up right, and replace the pump on the boiler. Taco OO

pumps can occasionally have "issues" and intermittent situations where

they will not start. If that happens, the boiler will bang and pop and

go off on high limit."



The Taco FlowCheck valve is OK if it is in the right way. The piping must be fixed, the green pump should be right side up. The black circulator is probably OK. It is pointing down, as it should be (pointing into the return of the boiler); it is probably the right size, because Weiil-McLain supplies the correct boiler circulator with the boiler, and the W-M supplied ones are painted black instead of Taco Green. If the U-control is set up right, the circulators are exercised for 10 seconds every 48 hours of inactivity.



"Also, if the outside sensor is not hooked up, have them do so and

program it for 140 minimum at 60 degrees F outside, and 180 degrees F

when the outside air is 0 degrees F."



If the outdoor sensor is not hooked up, it should be. It comes "free" with the boiler, and the U-control accepts it, so it is nuts not to use it. I suppose you could start with the settings Mark suggests, but I would not do that. It depends on the heat loss of your buildings and the heat emitters you are using. For example, I use 75F water in my radiant slab until it gets down to 52F, and then it slopes up until it gets to be 6F outside, by which time the temperature goes up to 120F. In my baseboard zone, with oversize emitters, it goes from 110F  until it gets down to 52F and slopes up to 135F when it is 6F outside. The fact that the two outside temperatures are the same is a coincidence.



When setting up the U-control board, you must specify the radiation being used. If you have copper fin-tube baseboard, for example, it will set 130F supply when it is 70F outside and 180F supply when it is 0F outside. This is the default. You can change those as I did. Similarly for radiant heat with an on-grade slab, it will set 120F supply when 0F outside and 80F supply when 70F outside. These would not work well for my house.



"You can down load the installation and maintenance manual on line, and see the correct way to install it."



Right. Here for Series 3:



http://www.weil-mclain.com/en/multimedia-library/pdf/weil-mclain-pdf/products/boilers/gas-boilers/ultra-series-3/ultra-series-3-boiler-manual.pdf



Here forSeries 3 UE:



http://www.weil-mclain.com/en/multimedia-library/pdf/weil-mclain-pdf/products/boilers/gas-boilers/ultra-series-3-ue/ug3_boiler_manual.pdf



By the way, "3) Recently the system cycles through a pre-purge / ignition /

post-purge (over and over) but does not ignite and heat.  Generally i

have to set the thermostat to no heat and them back to break the cycle."



This may be is a separate problem, and you will need someone familiar with W-M Ultra gas burners and controls to work on that.

Henry

Piping and Pumps

The boiler pump is pumping in the right direction. I am not sure if it is the right one as we stay away from the W/Ms. The P/S is not the way it should be done but can work. We have seen instances were the system pump is connected to an aquastat and then the boiler overheats as it cannot dissapate any heat as only the boiler pump works. This is not right. The system pump can be controlled by theboiler or preferably on all the time. The system pump looks much too large for an average home. It is probably causing the water noise. The gravity check needs to be removed.

The installer did not follow the manufacturer's instructions. He probably figured a larger pump is better for the system pump and did not calculate the flow and head rates.

In Canada, he had to leave teh I&O manual near the boiler as per code. You just have to look up the piping diagrams in there to see for yourself, how it should be done.

It is time to get someine who has installed many Mad/Cons to look at your installation.



Henry

Jean-David Beyer

Chances are that the boiler circulator is the right one.

"What size is the circulator on top of the unit (black one)?"



Chances are that it is the right size, because Weil-McLain supply the right size boiler circulator with the boiler, and thay have them painted black.



It looks as though it is in right side up. For an Ultra 3 115, the right size circulator is a Taco 0014. I cannot tell that from the picture.



Things to keep in mind.



1.) The U-control can accept three thermostat inputs. (I use all three.) These are priority 1 through 3. Priority 1 is the most likely one to be respondedto, and priority 3 the least likely. Typically, an indirect hot water heater is connected at priority 1, and if only one zone of heating, it is connected to priority 2.



2.) The U-control can drive up to three circulators. You are allowed to connect only one circulator to each output; if you need more, you must use a relay. Typically, the Indirect's circulator is connected to output 1. Typically the boiler circulator is connected to output 2, and typically the heating circulator is connected to output 3. If so, the default circulator settings will be correct. When the priority 1 thermostat is calling, circulator 1 will go on and the others will be off. When priority 2 thermostat is calling, circulator 1 will be off and the boiler circulator and the heating circulator will be on.



From the pictures, it is not clear how the unit is wired. I did find that there is a return sensor hooked up, probably correctly located. I do not know if it is wired correctly or not. I never found the supply sensor, and could not tell if the outdoor sensor is connected or not. I could not tell if the circulators are wired correctly. There should be a cable with the power from the boiler going into the top of the unit, and two cables for the power to the circulators.. I could find only two cables, unless they ran two through the same knock-out. If they did, I am not sure that is legal. Is not the plate on the main switch supposed to be red? All mine are wired with BX. I guess plastic is legal, but you might wish to make sure.

Jean-David Beyer

Comments.

Remember, I am a homeowner, not a heating professional. I have an Ultra 3 and have studied it a lot. I have read the installation manual cover to cover several times. I have also read John Siegenthaler's second edition from cover to cover a couple of times, and have started on the third edition. That is the context.



"The boiler pump is pumping in the right direction. I am not sure if it

is the right one as we stay away from the W/Ms."



It should be the right one, but it is easily checked. I say should be, because W-M supplies the boiler pump, and theirs are Tacos painted black.



"The P/S is not the way

it should be done but can work. "



I agree that it is not the way it should be done. I am not sure it will work as P-S because the Supply T is in sideways, which will cause resistance when the idea of P-S is to have no resistance between the Ts.



"We have seen instances were the system

pump is connected to an aquastat and then the boiler overheats as it

cannot dissapate any heat as only the boiler pump works. This is not

right. "



Mine has an aquastat because it is driving an in-slab heating zone that should not be overheated. W-M recommend one in the case where there are two zones operating at different temperatures. My system uses Taco 007s and runs at three temperatures: 170F for the indirect hot water heater, up to 135F for a baseboard zone, and up to 120F for the radiant one. So I have an aquastat on the radiant zone. It has never operated, however; it is just there for protection. If it opened, it would shut down the boiler , not just the circulator, until it closed, however, so this should not overheat anything, just shut off the heat until it reset.



"The system pump can be controlled by the boiler or preferably on

all the time."



In my system, it would be bad to have the circulator to the radiant zone on all the time, because it would try to circulate water that is too hot if the baseboard is calling for heat and the radiant zone circulator ran. Hence it must be controlled by the boiler and off when the baseboard zone is running.



"The system pump looks much too large for an average home.

It is probably causing the water noise. "



The O.P. seems to think it is air noise. He said it is an 007 Taco. My home is small; Cape Cod with about 30,000 BTU/hour heat loss when it is 0F outside. And design day is 14F. Now an 007, judging by the temperature drop between supply and return, is a little too big. Perhaps an 005 would be better. But not extremely so.





"The gravity check needs to be

removed."



Why? W-M specify one.





"The installer did not follow the manufacturer's instructions. He

probably figured a larger pump is better for the system pump and did not

calculate the flow and head rates.



Not clear to me. The P-S is not right, but otherwise it may be OK. Ugly, but OK. We do not know if he pumps away from the expansion tank. We do not know if he connected the outdoor reset. We do not know if he programmed the U-control correctly, we cannot tell if it is wired right. But it may be piped fairly well. We cannot be sure, though.



"In Canada, he had to leave teh I&O manual near the boiler as per

code. You just have to look up the piping diagrams in there to see for

yourself, how it should be done.



It is time to get someine who has installed many Mad/Cons to look at your installation."



That's for sure. I think it depends on location, but I would be incliend not to use a plumber, but a specialist in heating, and try to find one trained in installation and maintenance of W-M Ultra boilers. I had a lot of trouble locating such a contractor.

Mark Eatherton

Got me there JD....

I should have looked before I spoke regarding the gravity check. I have recently serviced/worked on 3 of these boilers, and NONE of them had a gravity check installed on them. Almost looks like W/Mc is stuck in old school mode as well, because none of the other M/C boiler manufacturers I deal with require a check valve in the boiler primary circuit, unless it is also doing prioritized DHW.



Personally, so long as it didn't void the manufacturers warranty, I'd eliminate it because I see no real benefit to it, other than trapping heat in the boiler, which is going to dissipate within the dwelling anyway...



Good catch.



ME

Jean-David Beyer

Flow check.

In the installation manual, W-M show a flow-check valve there in all their diagrams. However, in all cases, they show an indirect hot water heater also connected, also with a flow-check valve. In such a case you would want two as they show. Now without an indirect, piped across the primary (boiler) loop, you probably would not need either. But with one connected as they show, you might need something to keep the hot water heater from gravity heating the heating zones. Probably easier to put one in all their diagrams than to explain the fine points to people who are unable to read instruction manuals.



As far as trapping the heat in the boiler, W-M's controls on the Ultra 3 are such as to guard against this, and for good reason: the heat exchanger is not insulated. The heat exchanger in mine holds only 3 quarts of water, and when the thermostat is satisfied, the fire goes out, but the circulators run for 30 additional seconds to pump the heat out of the boiler and into the house or hot water heater. The 30 seconds is adjustable by the installer or homeowner. As I said in the previous paragarph, I think the flow check valves are to keep the indirect from heating the house by gravity flow

clammy

P/S piping

Aside from the probable pump issue as i see it the piping of theP/S  tee's are not correct and besides being oriented incorrectly the supply side will need a longer approach before tying to the central heat circ pump.I like to have at least 10 inches of straight pipe on each side of my P/S tees it guarantees that there is no other pressure drop in that area .I have seen issues where st 90,s where installed in the tees and there where issues with boiler short cycling on the hi limit even though the properly sized circ was being used for the specified mod con .As for the flow check i also always install one on the boiler supply as most mod con manufactures show and i also use a IFC circ usually pumping into the boiler .I also have seen issues on restrictivemod con boilers  where locating the pump pumping out of the boiler causing alot of thermal migration and also issues of short cycling i would guess from not enough flow due to the lower net available suction trying to suck through a tight  heat exhanger ? I think i would have those tees straightened out .Take a look at what the manafacture states in the installation and operations booklet and i an quite sure that it goes over the piping distance in detail in refrence to the distance of the tee apart from eaah other and the straight length of piping required before and after the tees and take it from there .Peace and god luck   clammy

Jean-David Beyer

i an quite sure that it goes over the piping

You are right about that. The installation manual has 10 full pages on piping a system with a single boiler, and 5 more pages on multiple boiler systems. These pages are profusely illustrated, with recommended minimum pipe sizes, maximum spacing of the closely-spaced Ts. They say the temperature sensors in the secondary loop should be at least 6 pipe diameters from the Ts, and not more than three feet from them. While the minimum pipe size I can use is 1 inch, my piping is 1 1/4" copper up there, and the Ts are 5 inches apart. So the minimum straight pipe should be 7 1/2 inches to each sensor, and their pictures imply that there should be no elbows or much else in that part of the piping. My system is slightlly short on the teturn side, and OK on the supply side.



The circulator supplied by W-M for the boiler circulator is a non-ifc model. I am not sure why it would need that check valve.

clammy

Check valves

The reason i see for a check on the boiler circ is so that if you where doing a indirect  so that you would pump through the boiler instead of out to the primary loop this is the reason for the check on the boiler pump .This being that there is less of pressure drop through the pump and it piping to the tee  then there is through the heat exchanger and water being so smart will always take the path of least resistances.I have seen this also happen and the tank will take longer to satisfy and there will be migrate heat and if you are running constant circulation on your central heating pump you will see over heating epically if you are running outdoor reset on lower then normal temps .This is why they give you all the piping diagrams they are trying to avoid all the issues but all those flow checks ,proper piping distances and throw in some isolation valve and the systems starts taking up some room.In tight installs i have started using hydro separator for the money they solve space issues and some piping distance to room issues but there is always more then one way to skin a cat peace and good luck clammy

Jean-David Beyer

More on check valves.

"The reason i see for a check on the boiler circ is so that if you where

doing a indirect  so that you would pump through the boiler instead of

out to the primary loop this is the reason for the check on the boiler

pump ."



The way W-M does the piping in P-S piped systems with indirect hot water heaters is to put the indirect across the boiler loop below the boiler circulator on the return to the boiler and below the Flow Check on the supply going up to the heating loop. When heating the house, they use the boiler circulator. When heating the indirect, the boiler circulator is turned off and a circulator (the same size as the boiler circulator) is used to circulate boiler water through the indirect. They want a flow check in the hot water loop as well, but my contractor used an IFC version of the taco there. It seems to work just fine. I cannot feel any gravity flow in any of the piping, although I recognize that this is not an accurate way to measure this.



"This being that there is less of pressure drop through the pump and it

piping to the tee  then there is through the heat exchanger and water

being so smart will always take the path of least resistances.I have

seen this also happen and the tank will take longer to satisfy and there

will be migrate heat and if you are running constant circulation on

your central heating pump you will see over heating epically if you are

running outdoor reset on lower then normal temps ."



I am not sure I understand you. Ignoring purge valves, etc., the return water goes first from the first of the closely separated Ts,  through the boiler circulator straight through the return T from the indirect into the return to the boiler. On the supply side, the water goes out of the boiler, straight through a T to the indirect, through the flow-check valve up to the second closely spaced T. When the boiler circulator is off, the flow-check will be closed, so water should not flow through that loop.



If the indirect is calling for heat, the boiler circulator will be off and the indirect circulator will be on. If there is any resistance at all in the boiler's heat exchanger, there will be a slight vacuum, if anything, at the input to the flow-check in the boiler loop, so the flow-check should remain firmly closed.



Now the return water from the indirect could be hotter than the water in the heating loop. But could much of the return water from the indirect flow backwards through the boiler circulator (without IFC) into the heating loop without a corresponding flow out of the heating loop back into the boiler loop? It cannot go back into the supply because of the flow- check valve. And the only way it could get back would be through the same pipe that it is going up to the heating loop. You could have a small gravity convection loop there, but since there is going to be a slight vacuum into the boiler return, I would suppose the return water from the indirect would prefer to go that way.



My indirect recovers so fast that I lowered the supply temperature from the default 190F to 170F. My heating zones can run between 75F and 135F, so I imagine the return from the indriect is always warmer than desired in the heating loop.



As far as low loss headers are concerned, they seem equivalent to closely spaced Ts to me. They have the advantage that they can combine the additional functions of dirt separation and air separation all in one unit, so piping may be more convenient. This could be an advantage if labor costs must be considered and for professionals, this is usually the case. Also in some circumstances (but not mine) it could make for a neater installation.

lchmb

nm

 

Kdg0363

Lots to digest

Thanks for the input.  I am printing out the posts to review and will comment after they are read.  From the quick glance, i wanted to include what i consider to be the correct piping diagram from the manual.  We are only running one zone and thus have the one 007 supply pump.  All are correct that the black pump was supplied with the unit.  I am quite certain that few if any calculations were made - so look for more requests for help there.  Also, the diagram shows a check valve.  As the warranty is now down to the heat exchanges, i am not too worried about removing it if that will help eliminate the problem.

Curious1

Ultra

This is just a side note.  Looks like the venting is sewer pipe..  Is that rated or certified for flue gases from water that is 200F?

Jean-David Beyer

Rated by whom?

Weil-McLain says to use it, or stainless, or some other plastic. I have the same kind of piping for combustion air and exhaust. I have run it  continuously since mid-May 2009. In non heating season, it supplies my hot water. W-M supply 190F +|- 5F to the indirect, and the return seems to be about 20F less most of the time. I have set mine to 170F. When it is running, I can feel warmth on the exhaust pipe, but it is by no means hot. Some day when it is making hot water, I will measure it with my infra-red thermometer. IIRC, three different inspectors examined my system and approved it.



It is my understanding that no plastic pipe manufacturer has approved their pipe for this use.

Del

pipe sizing

on these ultra boilers, I've noticed that the supply and return pipe stubs are 1", but depending on the size of the boiler, they want you to use 1", 1 1/4" or 1 1/2" for the primary loop.  Why aren't the stubs out of the boiler the proper size as well?  Is the size of the primary loop just to provide more water for the system circs to draw off of?



-Mike

Jean-David Beyer

W-M near boiler pipe sizing.

My only question is why the pipe sizing, in the boiler, is so small. Since the aluminum heat exchangers in the Ultra boilers are very small (mine is 3 quarts for the 80K BTU/hr model), they heat up very fast and they want to be sure there is enough flow through it. So if they need a large pipe in the near boiler piping, why not in the boiler as well?



My boiler requires at least 1-inch piping, but my contractor increased it to 1 1/4 inch after the pressure relief valve (and a LWCO on the return side, symmetrically). He said the boilers worked better that way. I have no way to tell, but the pressure drop between the closely spaced Ts should be less than with 1-inch pipe up there in the heating loop. He also spaced the Ts 5 inches apart, where W-M says 12 inches, maximum.



They use different heat exchangers in the different units, so they could have used the same size piping inside the boiler as they require outside it. If the amount of piping inside the boiler were very small compared with the piping outside the boiler, the resistance of the total loop would be determined mainly by the near boiler piping. But in my installation, the outside piping is about 5 feet, and the inside piping, including the heat exchanger, is about 5 feet as well. And the resistance of the heat exchanger may be more that that of an equivalent length of pipe.

icesailor

Ultra Closely Spaced Tees:

Notice how (in the drawing), the closely spaced tees are on a horizontal run with the tees rising on the vertical? That means that you aren't supposed to put one tee on a vertical riser and the other around the corner on the horizontal. I've seen this dons and it doesn't always work. Especially if you use a tee instead of an elbow for one side of the closely spaced tee and the other is less than 12" away.

Something about that drawing install picture made me think of that. It's hard for me to tell without actually seeing and touching it.

icesailor

Cleaned DWV Pipe:

The pipe isn't cleaned before cementing either which usually means that the end of the pipe wasn't chamfered. Which can wipe the cement out of the fitting.

In Massachusetts, inspectors can make you rip out the whole install, DWV plumbing AND gas venting if you don't clean.

If you don't clean the pipe, you shouldn't post a picture of it. It is WRONG and shouldn't be done.

Jean-David Beyer

The pipe isn't cleaned before cementing either

I wondered about that. If they used the cleaner with the purple dye in it, they used mighty little of it. There are cleaners (or there were, because I used them about 30 years ago) that are clear.



But purple is no assurance. My former contractor put in the same kind (different brand) of PVC. All the joints were purple. Unfortunately, after the cleaner, they forgot to put in any cement in most of the joinits. So after a while, the vent leaked and condensate got into the electronics and shorted out the U-control, locking out the boiler. It took a while to figure out the problem because those pipes were covered with thin black foam insulation (since removed). For various reasons, we replaced all the pipe, both combustion air and vent.



I asked the former contractor what the foam insulation was for. They said it was to prevent condensation from falling onto my car. That did not make sense to me. It also did not make sense to the W-M rep when he was here to investigate the lockout. By then, we knew there was water in there, but not where it was coming from.



It seems to me that installation of heating systems, electrical wiring, and probably everything else, requires a greater attention to detail than is commonly provided.

icesailor

Cleaning Pipe:

In Massachusetts, we aren't required to use purple primer. Thankfully. I hate the stuff. It doesn't work as well as clear.

But the clue to whatever is used, is to look for the manufacturerd stripe. It should be wiped off and mostly missing at the edge of the socket ot make in. There is usually at least 1/2" or more, depending on how far you run the cleaner.

The missing sement in the joint is usually caused by not chamfering the pipe. You MUST round over the end. Otherwise, the sharp edge of the pipe will wipe the cement out of the female part of the joint. It will also cut the softened PVC out of the fitting leacind no place for the solvent weld to take place.

Poor practices.

I was looking over a job with the owner and the plumbing inspector. SOmeone else had done the job. Because of the questions, even though it had been inspected by others, and there was no leaks that anyone was aware of. the inspector is demanding that the whole PVC DWV systenm be replaced because the pipe wasn't cleaned. There are other "issues" but this one could be a breaker for the owner.

CC.Rob

sizing?

155 is a pretty big boiler. Single zone with no indirect? Did anyone do a heat loss calc to size this?

mbarrett03

Similar Issue

I had a WM Ultra 155 and indirect DHW installed in January as well. We also have two residential heating zone circulators on priority 2. The DHW is a 45-gal SuperStore, and is piped off the primary return with a Taco 14 gpm ciruclator with 1'' pipes.  I read the manuals and this looks correct. 



The system worked great over the winter, but starting 3 weeks ago it starting locking out for a HIGH TEMP LIMIT fault.  That has happened five times over the past 3 weeks.  In all 5 cases the DHW was calling for heat when the boiler out 2 sensor hit 202 degrees. The default high temp limit for this machine is 200, hence the lockout.   The default output for the DHW on priority 1 is 190 with a max off and min on differential of 5 degrees, so this shouldn't happen.  I didn't notice any banging in the system though.



My installer came to look at it last week and said he didn't see anything wrong.  I called WM technical support today and they suggested the SuperStore DHW may have air in the coils.  My limited understanding is that the 155 has a small internal water capacity  (3 quarts I think), but has very high BTU output (123,000 BTU/h I believe).  Thus the system requires a high flow rate to circulate the cooler water through the DHW return, and carry the heat from the boiler out trough the supply to the DHW.  I guess the theory is that air in the DHW coils is reducing the flow rate of water through the boiler and it is resulting in the overheating.  If anyone could confirm that would be helpful.  We use hot water consistently so the DHW calls for heat at least once a day but it's only over heated 5 times, so it's pretty sporadic.  



My installer put a Spirovent air elimator on the secondary's return.  This seems to be consistent with the WM installation manual.  The only difference I can see is that my installer put the zone circulators on the return rather than the supply.  In either case I don't understand how the air eliminator, when installed on the secondary, would help to release air caught in the DHW.



WM also suggested we test the amps for the DHW circulator.  He said it should be between 1.4 and 2.  After speaking with WM I called my installer and told him that WM thought the likely cause was air in the Superstore coils so he is going to come by and help me purge it...hopefully this week. 



Also, I did notice that I can hear the sound of rushing water through the DHW circulator when it's calling for heat.  It's very noticeable.  Sounds just like rushing water, and occasional pings.   I don't notice that sound when the boiler is supplying heat for the residence when the primary ciculator (which is the as the DHW circulator) is running.   Not sure if that noise is an indication of air the system or not.  Would there be any other secondary indications of air in the lines which I might be able to notice?



Thanks.

Matt

Jean-David Beyer

Off limit with indirect.

"My limited understanding is that the 155 has a small internal water capacity  (3 quarts I think),"



4.68 quarts, actually. But small, nonetheless.



If you have the indirect across the boiler loop (the way W-M usually suggest), they want a Taco 0010 or 0012 depending on the indirect you have. For their indirects (tank-within-a-tank types) they suggest 0010 for the 40 and 60 gallon ones, and the 0012 for the larger ones. They want 1 1/4 inch pipe between the boiler and the indirect, not one inch. I am not competent enough to judge the effect of the smaller pipe; I would think it might reduce the recovery rate, but would be surprised if it would lead to overheating. The boiler circulator is a Taco 0014, and I would have thought they would specify the same for the indirect circulator, but they don't.



I am not a professional, and I am not there, but one guess I could make, and you should be able to check easily, is if the thermostat in your tank is stuck calling for heat, or if there is a short in the wiring so it is always calling for heat, or if it is turned up way too high. Then a call for heat would heat the indirect so hot that it could not sink the heat fast enough. With the W-M tanks (same as Triangle Tube, I believe), there is an automatic air vent at the top to let air out, since there is no other way to get the outer tank totally full.



Circulators on return rather than supply...? In the W-M installation manal, if you zone with circulators, they show them on the supply side, right after the expansion tank. If you put them at the other end of the heating loops, you can get a pressure reduction that can pull air in through the vent valves (if you have any) or leaks.



Is your indirect across the boiler loop? Or is it just one of the loads on the secondary loop? If the latter, you must ensure that the boiler loop circulator runs at priority 1 as well as priority 2..

mbarrett03

The indirect loop is off the primary

The DHW circulator is a Taco 14 which is the same model as the primary circulator.  I'll check on the piping to the DHW, I used a tape measure and guestimated the diameter at 1'', but it could be 1.25. As you can tell I have 0 plumbing experience.



I don't think the thermostat is stuck calling for heat.  It's set to 140, and typically recovers after 6-10 minutes. 



I noticed the WM diagram showing the zone circulators on the supply too, which is why i wanted to mention it.  Both my ciculators and are pulling from the return. I believe the expansion tank is also on the return. Thanks for the good info about this configuration possibly causing a pressure reduction that can pull air in through the vent valve. I will mention this to my installer as I believe air is definitely coming in from somewhere over time.  

Jean-David Beyer

When you find out, please let us know.

Since I am not a professional, but just curious, I would like to know what this ends up bieng. My system is smaller, but sounds pretty much like yours. I have an Ultra 3 80 with an 007 boiler circulator and an 007-IFC from the Indirect. When first turned on, I coul hear air in there, but it was removed fairly quickly by the tank-within-a-tank indirect. It sounded pretty much as I thought air would sound.



I do not know how much air it would take to cause your problem. It seems to me it would take quite a lot. But that may depend on what your indirect is like. If it is like the W-M and TriangleTube ones, the air should come out very fast. Same with a Turbomax or Ergomax. But the others I looked at would seem to need something like a Spirovent or Taco 4900 series in the line to the coil in the bottom of the tank to be sure of getting the air out, since systems piped like W-M show in their manuals have the air extractor in the secondary loop and air in the primary loop would be eliminated only slowly and only when the secondary loop(s) is running.

icesailor

Ultral Constant Problems:

My take on this (which isn't worth much).

I think that this is why Veissmann is so solidly insisting on hydraulic seperators on these applications.  In spite of the fact that the SSU 45 SuperStor is piped 1", the coil and connections are 3/4".  Restriction #1. Then, a high volume/head circulation to overcome the restriction. The "rushing water and pinging" is cavitation. A very bad thing. When you use hydraulic seperation, you may eliminate these problems.

You may not be able to do what I would try but if cavitation is a problem, turn up the system pressure. If it is 15# pressure on the gauge when it is cavitating, raise the system pressure with the by-pass lever until it gets to 25#. If the noise gets quieter or goes away, you stopped the cavitation. which is just water boiling around the impellors. Submarine props will cavitate and make noise. SONAR can hear it. The sub slows the prop down and dives deeper. It stops the noise. And the cavitation. The stronger the impellor design the greater chance of cavitation.

AFred

Um.....

Anyone going to complain about the expansion tank? OK I will! Its wrong.

-Andy

from minnesota....a purple primer state

mbarrett03

"since systems piped like W-M show in their manuals have the air extractor in the secondary loop and air in the primary loop would be eliminated only slowly and only when the secondary loop(s) is running"

...that was exactly what I was thinking.  It's been warm in New England the past few weeks so we haven't been running the heat in the house, hence not much circulation through the secondary and Spirovent which might explain the air buildup.



I may have been wrong about the expansion tanks, so I attached photos for the HH experts.  It looks like it's joined to the Sprirovent, which I think is joined to the secondary return as well as the inlet & flow valve.

mbarrett03

I will definetly let you know

once my installer is able to come out and take a look.  

icesailor

Um: Expansion devices

It may not be in the perfect place for some, but as far as I am concerned, as long as one is connected to the system, and it is or the proper size, and a #30 seems to fit most, I don't see what difference it makes where it is, as long as it is giving thermal hydronic expansion a place to go.

A far greater clue that needs an answer is the sound of rushing water in the pump.

If a heat generating source needs a certain flow rate and the system needs a certain flow rate, and the two aren't equal, strange things will happen. Hydraulic separation, which is the cousin to primary,secondary piping may be the answer. I've read about far too many problems with Ultra boilers. Perhaps a hydraulic separator, piped appropriately, would be a good solution.

Some of these boiler piping diagrams show the indirect as part of the boiler piping and the boiler pump runs through the indirect.

Jean-David Beyer

Relative location of circulators and expansion tanks.

"I don't see what difference it makes where it is,"



I see a difference where it is, depending on where the circulator(s) are. I have never read this book,



http://www.heatinghelp.com/products/Books/5/100/Pumping-Away-and-other-really-cool-piping-options-for-hydronic-systems



but my guess is it explains it pretty well. Similarly, Chapter 7, section 7.3 of the third edition of John Siegenthaler'e book, "Modern Hydronic Heating" explains it very well, including three diagarms, one correct and two incorrect, showing what happens if the circulators are improperly located.



"A far greater clue that needs an answer is the sound of rushing water in the pump. "



I think icesailor is right here. As a non-professional, I do not see why a little air in the system would hurt much, other than making annoying noises, and wearing out the circulators prematurely (that should be important), although a lot of air could prevent the circulator from circulating much of anything and burn out the bearings besides. So the sound of air (or cavitation) should be attended to promptly.



Most of W-M's installation diagrams have the indirects piped across the boiler loop. And they use the same size circulator for the indirect as they do for their main boiler circulator. So if the head of the near boiler piping, including the closely spaced Ts, or the hydraulic separator is about the same as the piping and head of the indirect, everything should be fine. The head through the W-M indirects is very low, and I know nothing about the SDuperstor. That is how it is with my Ultra 3 (small size). And I have no problems with it.



The only things that come to mind are that the piping to the Superstor may be a little too small (but even so, I do not see why the effect should be so extreme). The expansion tank and circulators do seem to be in the right place and seem to be on the supply side of the secondary loop. Could that flow-check valve on the return from the Superstor be in backwards or could it be stuck shut? If stuck shut, there would be a lot of head that the indirect circulator is not expecting that might cause cavitation. I do not know what cavitation sounds like.



There is supposed to be a flow check valve after the T that goes from the supply to the boiler off to the indirect and before it gets to the rightmost closely spaced T. It may be there, hidden by the exhaust vent from the boiler, but I do not see it. I do not believe that even if it is missing it would have anything to do with this problem.



Do you have a low water cut off in your system, or do you rely on the U-control to do this?

dano415

possible solution to the original problem?

   I'm not a professional,but I would make sure the vent and exhaust do not

have too many 90's and 45's.  Weil Mclain added an addendum on venting.

You are now allowed to inside air if your situation meets certain standards. 

(page A-20).

dano415

possible solution to the original problem?

   I'm not a professional,but I would make sure the vent and exhaust do not

have too many 90's and 45's.  Weil Mclain added an addendum on venting.

You are now allowed to inside air if your situation meets certain standards. 

(page A-20).